There are 209 different PBDE varieties, also called congeners. They are identical in molecular structure except that the number and/or position of bromine atoms in each congener vary. One of these congeners, pentabrominated diphenyl ether (penta), is a mixture containing congeners with four, five, and six bromine atoms. It was used extensively in polyurethane foam.

The manufacture of penta was banned by the European Union in 2003 and by the U.S. in 2004 because of increasing evidence of the congener’s toxicity in humans and other organisms. However, no import restrictions exist on products containing penta. Other countries can manufacture penta, add it to consumer products and sell those products in America.

Penta and other PBDEs accumulate in fatty tissues in animals of all kinds and can be passed from mother to child via breast milk. Even though penta was banned in the U.S, it is still present in homes, animals, humans and the environment because of its prevalence in furniture bought before the ban; its use in imported furniture and its apparent resistance to degradation. Other PBDE varieties such as octa and deca, used in plastic electronics casings such as for televisions, volatilize out of the plastic and into the air. They are banned in several states because they have been shown to cause liver toxicity, disrupt reproductive systems and cause endocrine disruption.

PBDEs sound like bad actors, but once upon a time they were the good guys. They replaced polychlorinated biphenyl (PCB) flame-retardants, which were banned by the United States Congress in 1976. PCBs, like PBDEs, are incredibly persistent: 30 years after the ban, PCBs are still found ubiquitously in mammals, human blood and umbilical cords, fish, birds, air, soil, lakes, rivers, house dust, sewage and wastewater sludge.

PCBs were used in coolants, insulating plasticizers, paints, cements, electrical wiring PVC coating, electronic components and pesticide extenders as well as in flame-retardants. Some industrial manufacturing areas are extremely contaminated with PCBs, such as the Hudson River, where fishing has been banned since 1976 due to the high levels of PCBs found in the river and fish. PCBs are considered especially deleterious because when burned, they react with oxygen and turn into the very toxic dioxin. PCBs are carcinogenic, decrease bone density in humans, increase behavioral and reflex problems in rats and decrease immune function in mice.

The basic structure of PCBs is similar to that of PBDEs. This is concerning because structurally similar molecules often have similar functions or modes of action in the human body. Both chemicals are also structurally similar to thyroid hormone, and animal studies have shown that PBDEs does in fact alter thyroid homeostasis.

PBDE flame-retardants look similarly to a known, banned toxin. They accumulate in humans and other animals, resist degradation, and exert toxic effects. The question remains, do they reduce the incidence of fire-related deaths?

A 2006 report by J. R. Hall, Jr. for the National Fire Protection Association shows from 1980 to 1999 states not requiring fire-retardants in furniture experienced the same decline in fire-related deaths that California did; flame-retardants have not displayed a measurable effect on the reduction of house fires. Arleme Blum, a Chemist from the University of California, Berkeley who researches extensively about flame-retardants, points out in a 2006 op-ed article for The New York Times, “most fatal furniture fires are caused by cigarettes, which typically smolder for half an hour after being put down.”

Recent legislation at the state level in many states across the nation mandates the manufacture of fire-safe cigarettes, which go out when set down due to “speed bumps” of thickened cigarette paper. Smoking materials such as cigarettes are the primary cause of fire deaths in the United States. If that threat is reduced, what use are toxic chemicals?

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First off, the title is poor since phosphorus based flame retardants have not been shown to have those toxicity problems so it should really read Brominated Flame Retardants.

Older forms of BFRs (Brominated Flame Retardants) are persistent, bioaccumulative, and toxic. That is the reason Pentabrom, PBDE, PCBs, and soon to be HBCD have been banned.

Many BFR products that companies push are much safer. Every new BFR product undergoes extensive toxicity testing that determines how safe it is. If it is determine unsafe, the product is dropped. Because of these earlier BFRs, these companies now know what to look for and avoid in future products.

Industry preference is actually for PFRs (Phosphorus-based Flame Retardants); however, some companies are unwilling to change from a product they know works, more PFR is usually required to have the same fire retardancy as BFRs, and PFRs may cost more than BFRs.

The main problem is this legacy of older bad products; but that happens with many industries. Yes, we need to deal with and clean up our mistakes. We didn't know it at the time, but now we have learned and we move on, just like anything else. If you burn your hand on the stove, you don't throw out the stove. You learn how to use it properly.

Flame retardants are also not really meant to prevent fires. Notice that the word retardant is used and not resistant or proof. FRs are designed to slow down the progression of fires and make the not burn as hot, which gives fire departments more time to respond and gives people more time to safely exit a house fire. The more time the fire department has, the fewer houses a fire may spread to.

So try to temper your articles with a bit of both sides. Your article is informative and well researched; however, you neglected to present the other side of the story which led to a very biased article.

Good post. The ultimate question is whether the risks outweigh the benefits. If not, watching your children burn to death is not a good alternative to the use of flame retardants. The article doesn't really answer the question for me.

A 2006 report by J. R. Hall, Jr. for the National Fire Protection Association shows from 1980 to 1999 states not requiring fire-retardants in furniture experienced the same decline in fire-related deaths that California did; flame-retardants have not displayed a measurable effect on the reduction of house fires.

The two halves of that sentence don't go together. The author's unstated assumption is that furniture manufacturers maintain two separate production lines. One production line is for furniture destined for California and other states requiring flame retardant. Furniture for all other states comes off of a separate production line where flame retardants aren't used.

More likely, furniture manufacturers maintain one production line, making the California law the de facto standard for the USA. The article admits that fires are in decline everywhere to a significant extent. The implication to me is that the stuff works. The hard, unanswered question is how the risks compare to the benefits.

Sorry, I thought the same thing at first, but if you look at the hyperlink in the beginning of the article. Zota et al. (1) shows that Californians have drastically higher levels of flame-retardants in their homes than others (for example Cape Cod). By the way, this article, the Zota one, is in an ACS (American Chemical Society) journal which means that it is considered a reputable journal by chemists. I feel the DT article could have made this more clear, but what ever. The polychlrinated biphenyl's are worse than the PDBE's if you ask me. Ph-Br bonds are typically weaker than Ph-Cl bonds and the fact it is an ether means that there are methods of turning it into a phenol as opposed to biphenyls where you are breaking a C-C bond, not nearly as easy as breaking a carbon heteroatom bond.

There is also the possibility that some furniture manufacturers do not sell in the state of California, and thus are not subject to that particular requirement. Also, some manufacturers may have different lines in various parts of the country to cut down on transportation costs and some products go to California or western states and some do not. These are plausible explanations for less amounts of fire retardants in parts of the country.

Also, that picture of the baby with chemicals is very sensationalistic. It is sort of like the filtrete commercial. That shows the baby and all of the evil bacteria and dust mites. IT is a play on peoples sensibilities, and is very intellectually dishonest, especially for an article that has a very serious and well researched, albeit still developing, in need of more research AND controvercial.

Ugh, helps if I make a complete sentence(grr...forgotten words and spelling errors)

IT is a play on peoples sensibilities, and is very intellectually dishonest, especially for an article that has a very serious and well researched topic, albeit still developing, in need of more research AND controversial.

Ugh, helps if I make a complete sentence(grr...forgotten words and spelling errors)

IT is a play on peoples sensibilities, and is very intellectually dishonest, especially for an article that has a very serious and well researched topic, albeit still developing, in need of more research AND controversial.